greg haygood

We started migrating from Frame Relay to MPLS this week. Decided to go with BGP routing during the turn-up, which sounded like it would be the easiest way. With traditional static routing, (I was told) our provider has to know about our network in order to get the packets to the right segment. With BGP, we manage our own routes and the provider's core doesn't have to be involved. Sounds perfect. I'm not a hardcore routing junkie, so it took a bit more effort than expected. But I did get it all figured out, and hope this will help someone else in the future.The basics of the network are that we have multiple offices connected via MPLS to our data center, which also provides Internet access for everyone. This lets us centralize and better manage the firewall and security policies. So each office and the data center has a Cisco 28xx router with a full T1 circuit. The current 12.4 GD and LD firmwares for the 28xx from Cisco don't include BGP capability, so we had to deploy with an ED release. We setup BGP routing on each router, using a single AS (autonomous system) number, for simplicity. The data center also has a DMZ network that is on a separate LAN segment from the WAN router. The serial IPs were assigned by our MPLS provider, and loopback IPs were assigned for convenience.Router Adata centerRouter Boffice #1Router Coffice #2Serial0/0/01.1.1.2/301.1.2.2/301.1.3.2/30FastEthernet0/010.1.1.1/2410.1.2.1/2410.1.3.1/24Loopback010.10.10.1/3210.10.10.2/3210.10.10.3/32DMZ Network10.10.1.0/24So the BGP configuration for each router looks like this:Router A (data center)<br /><pre><br />router bgp 65000<br /> no synchronization<br /> bgp log-neighbor-changes<br /> network 10.1.1.0 mask 255.255.255.0<br /> network 10.10.1.0 mask 255.255.255.0<br /> network 10.10.10.1 mask 255.255.255.255<br /> neighbor 1.1.1.1 remote-as 100<br /> neighbor 1.1.1.1 default-originate<br /> no auto-summary<br /></pre><br />Router B (office #1)<br /><pre><br />router bgp 65000<br /> no synchronization<br /> bgp log-neighbor-changes<br /> network 10.1.2.0 mask 255.255.255.0<br /> network 10.10.10.2 mask 255.255.255.255<br /> neighbor 1.1.2.1 remote-as 100<br /> no auto-summary<br /></pre><br />Router C (office #2)<br /><pre><br />router bgp 65000<br /> no synchronization<br /> bgp log-neighbor-changes<br /> network 10.1.3.0 mask 255.255.255.0<br /> network 10.10.10.3 mask 255.255.255.255<br /> neighbor 1.1.3.1 remote-as 100<br /> no auto-summary<br /></pre><br />